Positive action release hook



ug. 26, 1947, c. D. KARP Er Al. Y 2,426,221 l POSITIVE ACTION RELEASE HOOK Filed June v:50, 1945 2 sheets-'sheet 2 y INVENToRs. CHARLES ukARP JOSEPH I .BAcHMAN ATTORNEY jatented g. Y26, 15947 POSITIVE ACTIGN RELEASE HOOK Charles D. Karp and Joseph L. Bachman, Philadelphia, Pa.

Application June 30, 1945, Serial No. 602,634

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 9 Claims.

This invention relates to new and useful improvements in fastening devices, and more particularly to releasable fasteners of the hook type. Specifically, the invention relates to a release hook structure especially adapted for use with aircraft for releasably attaching thereto objects such as, for example, bombs, auxiliary fuel tanks, jet assist take-off units and similar equipment.

In military and other aircraft, bombs, auxiliary fuel tanks, jet assist take-off units and similar objects, adapted to be vcarried only temporarily by the plane, must be held positively and securely in place upon the plane until it is time for them to be released or jettisoned and, when released or jettisoned it is desirable that such objects be ejected or disengaged from the plane in a positive manner for safety and other purposes.

With this in mind, the principal object of the present invention is to provide a novel release hook structure for aircraft which issoperable to positively and securely retain an object therein ,until it is desired to release or jettison the same.

Another object of the present invention is to provide a novel release hook structure of the .stated character which is operable when the hook is actuated to release position to positively eject the object from the hook.

Another object of the invention is to provide a novel release hook having the features and advantages set forth which remains open and ready for reloading when actuated to release position, and which is operable automatically to lock and secure an ob-ject therein by the act of inserting an object into the release hook structure.

A further object of the invention is to provide a novel release hook structure of the character described which is of relatively simplified construction, comparatively inexpensive to manufacture and entirely efficient and fool-proof in use and operation.

These and other objects of the invention, and the various features and details of construction and operation thereof, are hereinafter fully set forth and described with reference to the accompanying drawing, in which:

Fig. 1 is a view in elevation showing a release hook structure embodying the present invention associated with the structural framework of an airplane.

Fig. 2 is a diagrammatic view of a release hook embodying the present invention showing the relative positions of the parts thereof when in locked position.

Fig. 3 is a View similar .to Fig. 2 showing the relative positions of the parts of the release hook upon actuation thereof to release position to eject an object held thereby, and

Fig. 4 is a view similar to Fig. 3 showing the relative positions of the parts of the release hook mechanism in position to receive an object to be held thereby.

Referring now to the drawing, and more pare ticularly to Fig. 1 thereof, reference numeral I designates generally a portion of the frame structure of an airplane, for example, the underside of the fuselage or a wing thereof. Associated with the frame structure I is a release hook structure, generally designated 2, made -in accordance with the present invention, and a hook structure 3 which is constructed, for example, as shown in the drawing. The said release hook 2 and the hook 3 constitute, respectively, the front and rear connections from which a bomb, auxiliary fue] tank, jet assist take-off, or a similar object 4, is adapted to be releasably suspended lor carried at the underside of the plane.

The present invention is concerned with the construction and operation of the forward release hook structure 2. Referring to Figs. 1 and 2 of the drawing, the release hook 2 may comprise a pair of side plate members 5 and 6, respectively, disposed in predetermined spaced parallel relation with respect to ,one another and suitably secured together in that relation by means of bolts or the like l. The spacing of the side plate merribers 5 and 6 may be accomplished by providing suitable bosses 8, for example, `on the inner face of one of the side plates as shown, although suitable washers or spacers may be employed f or this purpose as desired. The lower portions of the side plate members 5 and 6 of the release hook 2 are provided, respectively, with outwardly o-r rearwardly facing slots or recesses 9 that are correspondingly positioned in spaced, side by side relation, to form a forked hook portion I0 arranged to receive the forward attaching pin or ring II of an object 4 such as a bomb, auxiliary fuel tank, jet assist take-off, or the like in the manner shown in Fig. 1.

Mounted upon a stud l2 for pivotal movement between the side plate members 5 and 6 of the release hook 2, relative to the slots or recesses Il therein, is a latch member I3 having a locking arm portion I4 arranged, in one position of said latch member I3 to extend across the slots or recesses 9 and close the open side of the hook portion I0 and thereby retain in the said slots or recesses 9, and upon the hook portion I0, the forward attaching ring II of the object 4 as shown in Fig. 1 of the drawing. Y

The latch member I3 is held in the locking position just described by means of an elongated lever I5 having oppositely extending arm and finger portions I6 and I'I, respectively. The lever I5 is mounted intermediate said portions I6 and I'I upon a stud I8 for pivoted movement about said stud I8 between the plate members 5 and 6 of the hook structure 2. Locking of the latch member I3 in the position shown in Figs. 1 and 2 is accomplished Iby providing on the lever I5, intermediate its ends and adjacent the stud I8, a projecting portion I!! constructed and arranged `ing device II of the object 4. ring or attachment II of the object 4 -is thus 4ejected in a positive manner outwardly of the slots orfrec'esses 9 ofthe release hook structure 2, the

to engage a notch or recess 2 formed in the latch member I3. It is to be noted that the normal to the line of contact betwen the projection I9 of the lever I and the notch 20 of the latch member I3 passes close to the stud I8 constituting the axis of rotation of said lever I5, and hence the turning force is quite low and in a direction which tends to maintain the projection I9 engaged in the slot 20 of the latch member I3.

The arm portion I 6 of the lever I5 extends above the side plate members 5 and E of the hook structure 2, and connected to the outer end thereof is one end of a coil spring 2i which has its other end securely anchored to the frame structure I of the plane as shown. Also connected to this end of arm portion I 6 of the lever I5, through lsuitable ring connectors 22, is a cable or other control member 23 that leads to a point adjacent vthe station of the pilot, bombardier or other member of the flight crew, for actuation manually or otherwise, in the direction indicated by the arrow, to in turn actuate the lever I5 in a counter-clockwise direction about the stud I8 and 'against the restraining forc-e of the spring 2I ing with its projection I9 engaging the notch 25 in the latch member I3 thereby holding the latter inthe locking position until the control member 23 is actuated as described.

l Formed at the other side of the stud I2 from the locking arm portion I4 of the latch member I3 is a depending trigger portion 24 having the shape and configuration shown in the drawing and arranged for cooperative engagement by the previously mentioned finger portion Il of the 'lever I5 when the latter is pvoted about its stud I8 in counter-clockwise direction by actuation of the control member `23 as described. Thus, upon actuation of the control member V72% with resulting pivotal movement of the lever I5 in counterclockwise direction against the action of the spring 2l, the projection I9 of the lever I5 is disengaged from the notch or recess 20 in the latch member I3 and, as counter-clockwise rotation of Athe'lever I5 continues, the finger portion I1 thereof moves into engagement with the trigger por- Ytion 24 of the latch member I3 thereby likewise actuating the latter in a counter-clockwise direction.

As the latch member I3 moves in a counterclockwise direction from the position shown in -across the slots or recesses 9 as described, the

trigger portion 2-4 of the latch member I3 is Imoved by the linger I'I of'lever I5 lengthwise between the'slots or recesses 9 in an outward direction to the relative position shown in Fig. 3 of the drawing thereby serving to positively eject from the slots or recesses 9 the ring or other attach- As the forward rearward ring'or attachment 25 of the object 4 likewise vis moved rearwardly out of the slot or recess 42t `and free of the rearward hook 3.

In the relative positions of the lever I5 and latch I3 shown in Fig. 3 of the drawing, tension or pull upon the control member 23 has not yet been released to permit the spring ZI to return said lever I5 in a clockwise direction, and upon release of tension or pull upon the control member '23, the spring 2l will return the lever I5 in a clockwise direction to the position shown in Fig. 4 of the drawing with the surface 2l of the projecting portion I9v thereof engaging the surface of the arm portion I4 of the latch member I3 to thereby frictionally retain the latter in the position to which previously actuated with the trigger portion 24 thereof extending in or across the slots or recesses 9.

With the lever I5 and latch member I3 in the relative positions shown in Fig. 4, the release hook mechanism is in reloading position to receive therein another object 4 such as, for example, a bomb, auxiliary fuel tank, jet assist take-off unit, or the like, as the case may be. This may be accomplished by elevating the desired object 4 to be suspended from the hook structures 2 and 3 so as to position the ring or attaching devices II and 25 thereof adjacent the hook slots or recesses SI and 26, respectively, and then moving the object 4 so as to insert the ring attachments II and 25 into, or inwardly of, the slots 9 and 26, respectively.

As the ring attachment II of the object l is moved inwardly of the slots or recesses 9, it engages the projection 3I on the trigger portion 24 of the latch I3 thereby actuating the latter in clockwise direction about its stud IB and relative to the projecting portion I9 of the lever I5 until said projecting portion I5 clears the surface of the locking arm portion I4 0f the latch member I3 and engages again into the notch or recess 25 formed therein, the said latch member I3 and lever I5 resuming the relative positions shown in Figs. l and 2 of the drawing in which they are retained by the force of the spring 2i so that the locking arm portion I4 of the latch member I3 is positively held against displacement thus securely retaining the forward ring attachment I I of the object 4 upon the hook portion I5 of the structure 2. lThe fact that in the locked position of the structure the linger portion II of the lever I5 projects outwardly beyond the side plate members 5 and `6, as shown in Fig. 2, serves to indicate that the structure is in the locked position. Since the forward ring attachment II of the object 4 is retained securely in the slots or recesses `9 of the forward hook structure 2, the rearward ring or attachmentr 25 of the object 4 is retained and held against displacement from the slot 25 in the rearward hook structure 3.

From the foregoing it will be apparent that the present invention provides a novel release hook structure for bombs, auxiliary fuel tanks, jet assist take-off units and similar objects, adapted to be carried only temporarily by aircraft, which is operable to positively and securely retain such an object therein until it is desired to release or jettison same, and which isoperable when actuated to release position, to positively eject the object from the hook. The invention also provides al novel release -hook which when actuated to release position remains open and ready for-reloading, and which is operable automatically to lock and secure an object therein by the act of inserting an object into the release hookl structure. Furthermore, the invention proaforesaid features and advantages which is of relatively simplified construction, comparatively inexpensive to manufacture, and entirely eiicient and fool-proof in operation.

While a particular embodiment of the invention is illustrated and described herein, it is not intended that the invention be limited to such disclosure, and changes and modifications may be made therein and theretd Within the scope of the claims.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes Without the payment of any royalties thereon or therefor.

We claim: Y

l. A positive action release hook structure comprising a support including a hook, a latch member mounted on said support for pivotal movement and having a locking arm portion and a trigger portion arranged so that in one position of said latch member said locking arm portion is disposed crosswise of the hook opening to close the same and the trigger portion of said latch member is positioned clear of said hook opening, a lever member mounted on said support for pivotal movement and having a projection arranged to engage a recess in said latch member when the latter is in said one position, spring means tending to pivot said lever in one direction to maintain the projection thereof engaged With the recess in the latch member and positively secure the latter in said one position, and actuating means to pivot said lever in the opposite direction against said spring means to disengage the projecting portion thereof from the latch recess and cause the lever to engage the latch member and pivot the latter to retract the locking arm portion thereof from the hook opening to open the same and simultaneously move the trigger portion of said latch member into said hook opening to positively eject an object therefrom.

2. A positive action release hook structure comprising a support including a hook, a latch member mounted on said support for pivotal movement and having a locking arm portion and a trigger portion arranged so that in one position of said latch member said locking arm portion is disposed crosswise of the hook opening to close the same and the trigger portion of said latch member is positioned clear of said hook opening, a lever member mounted on said support for pivotal movement and having a projection arranged to a recess in said latch member when the latter is in said one position, spring means tending to pivot said lever in one direction to maintain the projection thereof engaged with the recess in the latch member and positively secure the latter in said one position, and actuating means to pivot said lever in the opposite direction against said spring means to disengage the projecting portion thereof from the latch recess and cause the lever to engage the latch member and pivot the latter to retract the locking arm portion thereof from the hook opening to open the same and simultaneously move the trigger portion of said latch member into said hook opening to positively eject an object therefrom, said spring means being operable upon release of said acuating means to pivot the lever in the reverse direction and engage the latch member to frictionally retain the latter in the position to which pivoted by the nger portion of said lever.

r3. A positive action release hook structure comprising a support including a hook, a latch member mounted on said support for pivotal movement and having a locking arm portion and a trigger portion arranged so that in one position of said latch member said locking arm portion is disposed crosswise of the hook opening to close the same and the trigger portion of said latch member is positioned clear of said hook opening, a lever member mounted on said support for pivotal movement and having a projection arranged to a recess in said latch member when the latter is in said one position, spring means tending to pivot said lever in one direction to maintain the projection thereof engaged with the recess in the latch member and positively secure the latter in said one position, and actuating means to pivot said lever in the opposite direction against said spring means to disengage the projection thereof from the latch recess and cause the lever to engage the latch member and pivot the latter to retract the locking arm portion thereof from the hook opening to open the same and simultaneously move the trigger portion of said latch member into said hook opening to positively eject an object therefrom, said spring means being operable upon release of said actuating means to pivot the lever in the reverse direction and engage the latch member to frictionallyretain thev latter in the position to which pivoted by the finger portion of said lever, and said trigger por-- tion of the latch member being actuable by theinsertion of an object into said hook opening to pivot the latch member in the reverse direction and reposition the locking arm portion thereof crossvvise of the hook opening and reengage the lever projection with the latch recess to thereby lock the latch member in said one position to retain the object in said hook opening against displacement therefrom.

4. A positive action release hook structure comprising a support including a bifurcated hook, a latch member mounted on said support for pivotal movement and having a locking arm portion and a trigger portion arranged so that in one position of said latch member said locking arm portion is disposed crossvvise of the hook opening to close the same and the trigger portion of said latch member is positioned clear of said hook opening, a lever member mounted on said support for pivotal movement and having oppositely extending arm and linger portions and an intermediate projection, said projection being arranged foi` engagement with a recess in said latch member when the latter is in said one position, spring means tending to pivot said lever in one direction to maintain the projection thereof engaged with the recess in the latch member and positively secure the latter in said one position, and actuating means to pivot said lever in the opposite direction against said spring means to disengage the projection thereof from the latch recess and cause the lever finger portion to engage the trigger portion of the latch member and pivot the latter to retract the locking arm portion thereof from the hook opening to open the same and simultaneously move the trigger portion of said latch member into the hook opening to positively eject an object therefrom.

5. A positive action release hook structure comprising a support including a latch member mounted on said support for pivotal movement and having a locking arm portion and a trigger portion arranged so that in one position of said latch member said locking arm portion is disposed crosswise of the hook opening to close the same and the trigger portion of said latch member is positioned clear oi said hook opening,A a lever member mounted on said support for pivotal movement and having oppositely extending arm and nnger portions and an intermediate projection, said projection being arranged for engagement with a recess in said latch member when the latter is in said one position, spring means tending to pivot said lever in one direction to maintain the projection thereof engaged with the recess in the latch member and positively secure the latter in said one position, and actuating means to pivot said lever in the opposite direction against said spring means to disengage the projection thereof from the latch recess and cause the lever ringer portion to engage the trigger portion of the latch member and pivot the latter to retract the locking arm portion thereof from the hook opening to open the same and simultaneously move the trigger portion of said latch member into said hook opening to positively eject an object therefrom, said spring means being operable upon release of said actuating means to pivot the lever in the reverse direction and engage the locking arm portion of the latch member to frictionally retain the latter in the position to which pivoted by the finger portion of said lever.

6. A positive action release hook structure comprising a support including a latch member mounted on said support for pivotal movement and having a locking arm portion and a trigger portion arranged so that in one position of said ilatch member said locking arm portion is disposed crosswise of the hook opening to close the same and the trigger portion of said latch member is positioned clear oi said hook opening, a lever member mounted on said support for pivotal movement and having oppositely extending arm and iinger portions and an intermediate projection, said projection being arranged for engagement with a recess in said latch member wheny the latter is in said one position, spring means tending to pivot said lever in one direction to maintain the projection thereof engaged with the recess in the latch member and positively secure the latter in said one position, and actuating means to pivot said lever in the opposite direction against said spring means to disengage the projection thereof from the latch recess and cause the lever finger portion to engage the trigger portion of the latch member and pivot the latter to retract the locking arm portion thereof from the hook opening to open the same and simultaneously move the trigger portion of said latch member into said hook opening to positively eject an object therefrom, said spring means being operable upon release of said actuating means to pivot the lever in the reverse direction and engage the locking arm portion of the latch member to frictionally retain the latter in the position to which pivoted by the linger portion of said lever, and said trigger portion of the latch member being actuable by the insertion of an object into said hook opening to` pivot the latch member in the reverse direction and reposition the locking arm portion thereof crosswise of the hook opening and reengage the lever projection with the latch recess to thereby lock the latch member in said one position to retain the object in said hook opening against displacement therefrom.

7. A positive action release hook structure comprising a pair of plate members secured together in predetermined spaced parallel relation and having open ended slots therein correspondingly positioned to denne a bifurcated hook, a latch member mounted for pivotal movement intermediate said `plate members and having a locking arm portion and a trigger portion arranged so that in one position of said latch member said locking arm portion is disposed crosswise of the open ends of said' slots to close the saine and the trigger portion of said latch member is positioned clear of saidslots, a lever member mounted for pivotal movement intermediate said plate members and having oppositely extending arm and finger portions and an intermediate projection, said projection being arranged for engagement with a recess in said latch member when th'e latter is in said one position, spring means tending to pivot said lever in one direction to main` tain the projection thereof engaged with the recess in the latch member and positively secure the latter in said one position, and actuating means to pivot said lever in the opposite direction against said spring means to disengage the projection thereof from the latch recess and cause the lever ngerportion to engage the trigger portion of the latch member and pivot the latter to retract the locking arm portion thereof from the slots to open the same and simultaneously move the trigger portion of said latch member outwardly between the slots to positively eject an object therefrom.

8. A positive action release hook structure comprising a pair of plate members secured together in predetermined spaced parallel relation and having open ended slots therein correspondingly positioned to denne a bifurcated hook, a latch member mounted for pivotal movement intermediate said plate members and having a locking arm portion and a trigger portion arranged so that in'one position of said latch member said locking arm portion is disposed crosswise of the open ends of said slots to close the same and the trigger portion of said latch member is positioned clear of said slots, a lever member mounted for pivotal movement intermediate said plate members and having oppositely extending arm and finger portions and an intermediate projection, said projection being arranged for engagement with' a recess in said latch member when the latter is in said one position, spring means tending to pivot said lever in one direction to maintain the projection thereof engaged with the recess in the latch member and positively secure the latter in said one position, and actuating means to pivot said lever in the opposite direction against said spring means to disengage the projection thereof from the latch recess and cause the lever nger portion to engage the trigger portion of the latch member and pivot the latter to retract the locking arm portion thereof from the slots to open the same and simultaneously move the trigger portion of said latch member outwardly between the slots to positively eject an object therefrom, said spring means being operable upon release of said actuating means to pivot the lever in the reverse direction and engage the locking arm portion of the latch member to frictionally retain the latter'in the position to which pivoted by the finger portion of said lever.

9. A positive action release hook structure comprising a pair of plate members secured together in a predetermined spaced parallel relation and having' open `ended slots therein correspondingly positioned to denne a bi'furcated hook, a latch member mounted for pivotal movement intermediate said plate members and having'a locking arm portion and a trigger portion arranged so that in one position of said latch member said 9 locking arm portion is disposed crosswise f the open ends of said slots to close the same and the trigger portion of said latch member is positioned clear of said slots, a lever member mounted for pivotal movement intermediate said plate members and having oppositely extending arm and finger portions and an intermediate projection, said projection being arranged for engagement with a recess in said latch member when the latter is in said one position, spring means tending to pivot said lever in one direction to maintain the projection thereof engaged with the recess in the latch member and positively secure the latter in said one position, and actuating means to pivot said lever in th'e opposite direction against said spring means to disengage the projection thereof from the latch recess and cause the lever nger portion to engage the trigger portion of the latch member and pivot the latter to retract the locking arm portion thereof from the slots to open the same and simultaneously move the trigger portion of said latch member outwardly between the slots to positively eject an object therefrom, said spring means being operable upon release of said actuating means to pivot the lever in the reverse direction and engage the locking arm portion of th'e latch mem- CHARLES D. KARP. JOSEPH L. BACHMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,400,248 Morgan s May 14, 1946 FOREIGN PATENTS Number Country Date 259,688 Italy July 25, 1928 335,582 Italy Feb. 6, 1936 

